<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>伪元素</title>
  <style>
  .container {
    max-width: 600px;/*  适配 移动端用自己的宽度 PC 端 mw */
    margin:0 auto; /*左右水平居中*/
    padding: 20px;
    font-family: Arial, sans-serif;
  }
  h1 {
    text-align: center;
  }
  p {
    line-height: 1.6;
  }
  .more {
    /*格式化上下文 定义元素的布局规则*/
    display: inline-block;
    padding: 10px 20px;
    background-color: #007bff;
    color:white;
    text-decoration: none;
    position: relative;
    transition: all .3s ease;
  }
  .more::before {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 2px;
    background-color: yellow;
    transform: scaleX(0);
    transform-origin: bottom left;
    transition: transform .3s ease;
  }
  .more:hover::before {
    transform: scaleX(1);
  }
  .more::after {
    display: inline-block;
    content: "\2192";
    margin-left: 5px;
    transition: transform .3s ease;
  }
  .more:hover::after {
    transform: translateX(5px);
  }
  </style>
</head>
<body>
  <div class="container">
    <h1>示例标题</h1>
    <p>这是一个段落，</p>
    <a href="#" class="more">查看更多</a>
  </div>
</body>
</html>